Looper mechanism for hooked-needle sewing-machines.



E P. W. MBRRIGK.

LOOPER MECHANISM EORHOOKED NEEDLE SEWING MAGHINES. APPLICATIONy FILED MAY 31, 1906.

946565 L, Patented Jan. 11, 1910.

2 SHEETS-SHEET 1.

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@KM @MM 5M WY. Svgmdm P. W. MERRIGK l LOOPEB. MECHANISM POR HOOKED NEEDLE SEWING MACHINES.

APELICATIN FILED MAY 31, 1906.

UNITED STATES PATENT OFFIQE.

FRANK W. MERRICK, 0F BOSTON, MASSACHUSETTS, ASSIGNOR TO UNION LOCK STITCI-I COMPANY, OF BOSTON, MASSACHUSETTS, A CORPORATION OF MAINE.

LOOPER MECHANISIII FOR I-IOOKED-NEEDLE SEWING-MACHINES.

To all whom it may concern:

Be it known that I, FRANK YV. MERRICK, a citizen of the United States, residing at Boston, in the county of Suffolk, State of Massachusetts, have invented a certain new and useful Improvement in Looper Mechanism for Hooked-Needle Sewing-Machines, of which the following is a specification, reference being had therein to the accompanying drawings.

The invention relates to the mechanisms by which in hooked needle sewing machines the thread used in the formation of a stitch is laid in a loop within the open eye of a hooked needle and about the needle, in readiness for being taken by the latter through the material which is being stitched.

The general object of the invention is to provide a looper mechanism of simple construction adapted to be operated at very high rates of speed, without noise or excessive vibration, and in which the movement shall be positive throughout. One particular object thereof is to provide for taking up all play and lost motion.

The invention is illustrated in the drawings in the best forms of embodiment thereof which I have yet contrived.

Only so much of a sewing machine is shown as is required to make clear the nature and relations of the invention.

In the drawings,-Figure l shows in front elevation a portion of a sewing machine having one of the embodiments aforesaid applied thereto; Fig. 2 is a view in section along the dotted line 2, 2, of Fig. l, looking in the direction indicated by the arrows at the ends of such line, the work-support, needle-bar, and needle-post being omitted. Fig. 3 is a view in section along the dotted line 3, 3, of Fig. l, looking in the direction indicated by the arrows at the ends of such line. Fig. l is a sectional detail showing the means and manner of supporting the swivelfollower upon the arm of the yoke to which it is applied. Fig. 5 is a front elevation showing a second embodiment. Fig. 6 is a view looking from the left hand side in Fig. 5. Fig. 7 is a sectional detail of the embodiment shown in Figs. 5 and 6.

Having reference to the drawings,-At l, Fig. l, is shown a portion of the overhanging arm which forms part of the fixed frame of a sewing machine, at 2 the driving-shaft mounted in bearings in the said arm, at 8 a Specification of Letters Patent.

Application filed May 31, 1906.

Patented aan. ii, raro.

Serial No. 319,435.

portion of the work-support, at 4; a portion of the needle-post, and at l1 a portion of the needle-bar. At 5, Figs. l, 2, and 3, is shown a hooked needle carried by the said needle-bar, and at G is the looper by which the thread used in the formation of the stitches is laid in the open eye of the needle and around the latter, as usual. At 6l, in the said figures, is a yoke having a downwardly-extending arm 611 provided with a split clamp within which the stem of the looper is received, the said clamp being tightened upon the said stem by means of a pinchscrew 612. The yoke is placed around the T-shaped head of a rocker 63 having the body-portion thereof constituted by a small rockshaft. The said rockshaft extends parallel with driving-shaft 2 and has a journalportion that is mounted in a bearing in a lug 631 depending from the under side of the arm 1. The yoke is mounted pivotally upon the head of the rocker by means of center-screws 62, 62, applied to the front and rear ends of the yoke and engaging with the front and rear ends of the said head. The yoke is capable of turning upon the said center-screws in the direction of the length of the rocker, so as to swing the looper back and forth in such direction, and the rocker itself is capable of turning around its longitudinal axis, so as to move the yoke and looper from front to rear and vice versa. It will be perceived that the described means of supporting the looper constitutes in effect a universal-joint mounting therefor. That is to say, the said mounting enables the looper to be swung universally in all directions.

For the purpose of communicating to the looper the movement by which it is caused to travel in the required pat-h about the needle, the yoke 6l is provided with an arm 64 extending upwardly therefrom and provided with a swivel-follower 65 which works in a cam-groove 66 which is formed in the periphery of a cam-hub 67 that is fixed upon driving shaft 2. The walls of cam-groove 66 have transverse throws extending axially with respect to the driving-shaft, as shown in Fig. l; also, radial-grades, as indicated in Fig. 2. In the rot-ation of shaft 2 and cam-hub 67, the said transverse or axial throws operate to swing the arm 64, yoke 61, and looper 6, about the axes of the center-screws at 62, 62, in the direction of the length of shaft 2, that is to say, transversely or from right to left and vice versa in Fig.

1, and the radial grades operate to turn the said parts, and the rocker 63 as well, around the axis of the rocker in a direction at right angles to the said axis, that is to say, from front to rear and vice versa in Fig. l. Thereby the looper is caused to travel in the predetermined path about the needle, to lay the thread about the needle and within the open eye thereof.

ln order to obviate the necessity for the use of a spring acting in opposition to the radial grades of the walls of the cam-grooves 66, to hold the follower 65 in contact with the said walls and produce the return movement of the looper after the same has been moved in one direction by the said grades, I provide a complementary cam 7, and tix upon rocker 63 an arm 8 which is engaged by the said cam 7. The complementary cam 7 is constructed to hold the follower 65 in contact with the walls of the cam-groove 66 and is formed with radial grades which act positively to produce the return movement of the rockerA and looper, the arm S'being caused to engage with complementary cam 7 at the opposite side of the axis of drivingshaft 2 from that at which the follower 65 of arm 64 is engaged with cam 67. Rocker 63 thus is rocked by cam 67 to produce the swinging movement of the looper in one direction, and by complementary cam 7 to produce the swinging movement of the looper in the opposite direction, while the axial throws of the said acting portions produce the movements in directions at right-angles to those first described. The resultant of the component movements thus occasioned is the required curvilinear path of travel of the delivery-eye of the looper about the needle.

The looper 6 is held positively at all times by the cams 67 and 7. The complementary cam 7 acts positively to hold follower 65 in constant engagement with the acting portions of cam 67, as well as to restrain the rocker and looper from radial overthrow due to the action of the cam 67 at high speed, and to produce the return movements thereof.. The attainment of an exceedingly high rate of speed thereby is rendered practicable. If a spring were depended upon in place of the complementary cam, the radial overthrow at high speed would produce excess of turning movement of the rocker, and would render the movements of the looper irregular and uncertain.

For purposes of adjustment, to take up play and lost-motion, arm 8 is mounted upon rocker 63 with capacity for angular adjustment relative to the said rocker, toward and from the arm 64. To this end, the rocker is slabbed oif at opposite points, as shown in Fig. 3, and two adjusting or set-screws 9, 9, are fitted to threaded holes which are tapped ends of the said screws take against the [lat faces of the rocker, at opposite points with respect to each other. .y properly turning the said screws, the arm t3 may be angularly adjusted around the axis of rocker 63, and thereby be set closer to the arm 64, as may be required for taking up play or lost-motion between the arms and the cams.

The cam-follower 65 is in universal swiveljoint connection with the looper carrier, it being, in the illustrated embodiment of the invention, supported upon arm 64 by means of a ball and socket mounting, allowing it freedom to rock and swivel in all directions to accommodate itself at all times to the acting portion of the cam 67 and to the varying positions of the arm 64. This mounting is shown in Fig. 4. Having reference to the said figure, in which the portion of the follower that works in cam-groove 66 is V- shaped in cross-section, to correspond with the V-shape of the cam-groove, the follower is formed at its back with a spherical cavity or socket 661 receiving the spherical head 642 of a pin 641 carried by arm 64. Pin 641 is shouldered at 648, adjacent its head 642, and is applied to arm 64 by placing its stem within a hole that is made in the said arm, with the shoulder of the pin in contact with the inner side of the arm.

ln the embodimentof the invention which is shown in Figs. 5, 6. and 7, the rocker is constituted of a block around which the yoke 61 is placed, with the center-screws 62, 62, in engagement with the front and rear ends of the block. The said block 9 is supported by a stud 10 which is fixed by the screw 11 in the lug or projection 631 of the arm 1, the block being kept in place upon the said stud by means of an enlarged head with which the stud is provided, the said head being conical or tapered and the hole through the block being correspondingly shaped. The arm S is secured to the rear side of the block by means of screws 81, 81, passing through the said arm and into threaded holes which are tapped in the block, one above the other. For purposes of adjustment the portion of the arm which makes contact with the block is rounded vertically so as to permit the said arm to be adjusted upon the block toward or from the arm 64 by manipulating the respective screws 81, 81, to cause the said portion of arm 8 to rock more or less upon the block.

1 claim as my invention l. In looper-mechanism for hooked-needle sewingmachines, in combination, a looper' provided with a cam-follower, a rocker on which the looper is mounted to swing about an axis at an angle to that on which the rocker turns, a supporting bearing for said rocker, an actuating cam having radial grades and also transverse in the hub-portion of the arm 8. The inner throws engaging with the cam-follower to traverse the delivery-eye of the looper in an orbital path about the needle, and a complementary cam in operative control of the rocker acting positively to restrain the latter from radial overthrow and to produce the return movement thereof.

2. In looper-mechanism for hooked-needle sewing-machines, in combination, a looper provided with a cam-follower, a rocker on which the looper is mounted to swing about an aXis at an angle to that on which the rocker turns, a supporting bearing for said rocker, an actuating cam having radial grades and also transverse throws engaging with the cam-follower to traverse jthe delivery-eye of the looper in an orbital path around the needle, an arm in connection with the said rocker, and a complementary cam engaging with the said arm and acting positively to restrain the rocker from radial overthrow and to produce the return movement thereof.

3. In looper-mechanism for hooked-needle sewing-machines, in combination, a looper provided with a cam-follower, a rocker on which the looper is mounted to swing about an aXis at an angle to that on which the rocker turns, a supporting bearing for said rocker, an actuating cam having radial grades and also transverse throws engaging with the cam-follower to traverse the delivery-eye of the looper in an orbital path around the needle, an arm upon the said rocker, a complementary cam engaging with the said arm of the rocker and acting positively to restrain the rocker and looper fromv radial overthrow and to produce the return movement thereof, and means to effect angular adjustment of the said arm relative to the aXis of the rocker.

4. In looper-mechanism for hooked-needle sewing-machines7 in combination, a looper, a looper-carrier, a cam-follower in universal swivel-joint connection with said looper-carrier, a universal-joint mounting for the said looper-carrier, and an actuating-cam having a cam-track formed with radial grades and also transverse throws which act upon said cam-follower to traverse the said looper in an orbital path around the needle.

5. In looper-mechanism for hooked-needle sewing-machines, in combination, Va looper, a looper-carrier, a cam-follower V- shaped in cross-section having ball-andsocket connection with said looper-carrier, a universal-joint mounting for the said looper-carrier, and an actuating-cam having a V-shaped cam-track formed with radial grades and also transverse throws.

In testimony whereof I affix my signature in presence of two witnesses.

FRANK IV. MERRICK.

Vitnesses:

CHAs. F. RANDALL, EDITH J. ANDERSON. 

